Main Bearing Kit - Fits Volvo Penta 4-Cylinder AQ & B Series (Replaces 270906)
Main Bearing Kit - Fits Volvo Penta 4-Cylinder AQ & B Series (Replaces 270906) is backordered and will ship as soon as it is back in stock.
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Worry-free returns
Worry-free returns
You may return most new, unopened items within 7 days of delivery for a full refund. We'll also pay the return shipping costs if the return is a result of our error (you received an incorrect or defective item, etc.).
You should expect to receive your refund within four weeks of giving your package to the return shipper, however, in many cases you will receive a refund more quickly. This time period includes the transit time for us to receive your return from the shipper (5 to 10 business days), the time it takes us to process your return once we receive it (3 to 5 business days), and the time it takes your bank to process our refund request (5 to 10 business days).
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Delivery and Shipping
Delivery and Shipping
Free standard shipping on all orders under 1 KG
Main Bearing Kit - Fits Volvo Penta 4-Cylinder AQ & B Series (R...
Product Details
This is a standard-sized crankshaft Main Bearing Kit - Fits Volvo Penta 4-Cylinder AQ & B Series for gasoline engines. It is designed for Volvo Penta B200, B230, and B234 series engines found in AQ131, AQ151, AQ171, 230, 250, and 251 models manufactured between 1987 and 1989.
This kit serves as a direct replacement for Volvo Penta 270906, Orbitrade 11906, NPR Europe RD270906S, and Glyco 270906, providing a reliable alternative for engine rebuilds.
- Installs directly into the engine block.
- Compatible with engines using a 63mm diameter crankcase.
- Engineered for gasoline fuel systems.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Volvo Penta | 270906 |
| Orbitrade | 11906 |
| NPR Europe | RD270906S |
| Glyco | 270906 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
This kit is compatible with the following Volvo Penta marine engines:
| Brand | Model | Stroke | Years | OEM Part No. |
|---|---|---|---|---|
| Volvo Penta | AQ131C | 4-Stroke | 1987–1989 | 270906 |
| Volvo Penta | AQ131D | 4-Stroke | 270906 | |
| Volvo Penta | AQ151C | 4-Stroke | 270906 | |
| Volvo Penta | AQ171C | 4-Stroke | 270906 | |
| Volvo Penta | 230A | 4-Stroke | 270906 | |
| Volvo Penta | 230B | 4-Stroke | 270906 | |
| Volvo Penta | 250A | 4-Stroke | 270906 | |
| Volvo Penta | 250B | 4-Stroke | 270906 | |
| Volvo Penta | 251A | 4-Stroke | 270906 |
These bearings are also used in various Volvo car models equipped with the B200, B230, and B234 series engines.
| Brand | Model | Engine | Stroke | Years | Notes |
|---|---|---|---|---|---|
| Volvo | 240 | B200, B230, B234 | 4-Stroke | 1988+ | Std. size |
| Volvo | 340 | B200, B230, B234 | 4-Stroke | 1988+ | Std. size |
| Volvo | 360 | B200, B230, B234 | 4-Stroke | 1988–1989 | |
| Volvo | 740 | B200, B230, B234 | 4-Stroke | 1988+ | Std. size |
| Volvo | 760 | B200, B230, B234 | 4-Stroke | 1988+ | Std. size |
| Volvo | 780 | B200, B230, B234 | 4-Stroke | 1988+ | Std. size |
| Volvo | 940 | B200, B230, B234 | 4-Stroke | 1991+ | Std. size |
| Volvo | 960 | B200, B230, B234 | 4-Stroke | 1991+ | Std. size |
Technical Specs
- Product Type
- Crankshaft Main Bearing Set
- Installation
- Engine Block
- Fuel Type
- Gasoline
- Dimensions
- 15.5cm (L) x 11.5cm (W) x 12.0cm (H)
- Other Technical Attributes
- Standard size bearings for engines with 63mm diameter crankcase
What’s in the Box
- Crankshaft bearing halves (Replaces 270906)
Installation Notes
- Disconnect the battery and safely drain all engine fluids (oil and coolant).
- Remove the oil pan and oil pump to gain access to the crankshaft.
- Carefully remove the main bearing caps one at a time, keeping them in order.
- Remove the old upper and lower bearing halves from the block and caps.
- Thoroughly clean the crankshaft journals, bearing saddles, and caps. Ensure no debris remains.
- Apply a liberal amount of engine assembly lubricant to the new bearing halves.
- Install the new upper bearing halves into the engine block and the lower halves into the caps.
- Carefully reinstall the main caps in their original positions and torque the bolts to the manufacturer's specified sequence and values.
- Check for proper crankshaft rotation after torquing each cap.
- Reinstall the oil pump and oil pan with new gaskets.
- Refill the engine with the correct type and amount of oil, then reconnect the battery.
- Prime the oil system before starting the engine to ensure immediate lubrication.
Troubleshooting & FAQ
How do I know if my main bearings are failing?
Common signs of worn main bearings include a deep, knocking sound from the engine that increases with RPM, low oil pressure readings, and the presence of metallic particles (bearing material) in the engine oil during an oil change.
What is the difference between main bearings and connecting rod bearings?
Main bearings support the crankshaft within the engine block. Connecting rod bearings (or "big end" bearings) are located at the crankshaft end of the connecting rods. This kit is for the main bearings only.
Is this kit for a standard size crankshaft?
Yes, this is a standard-sized bearing set. It is not for crankshafts that have been machined undersize. Always measure your crankshaft journals to confirm the required bearing size before ordering.
Can I reuse my old main bearing cap bolts?
It is generally recommended to replace main bearing cap bolts, especially if they are torque-to-yield (TTY) bolts, as they are designed for one-time use. Refer to your engine's service manual for specific guidance.
Do these bearings require any special preparation before installation?
The bearings should be clean and free of any debris. Before installation, they must be thoroughly lubricated with a high-quality engine assembly lube on the surface that contacts the crankshaft journal.
How many bearing halves are included?
This kit includes a complete set of bearing halves required for the crankshaft. The exact quantity varies depending on the specific engine configuration, but it will be sufficient for a full replacement.
Is this an OEM part or aftermarket?
This listing is an aftermarket replacement (not OEM). It is built to OEM-level specifications with comparable materials. Manufactured in an ISO 9002 facility, our parts are batch-inspected for consistency and quality.
What are the shipping speed and cost?
We ship worldwide quickly—typical transit is 5–15 days. Standard shipping is free; expedited options appear at checkout where available, with costs calculated based on your location.
What is the warranty and return policy?
Our products are covered by a 1-year warranty against manufacturing defects under normal use. If an issue arises, contact our support team with your order details. Returns are accepted within our standard window, provided the item is unused and in its original condition. See our policy page or reach out for instructions.
Safety & Important Info
- Verify images and specifications against your original part before purchasing. If anything differs—even if your model appears compatible—do not purchase.
- This is an aftermarket replacement part, not an OEM component. Brand names and part numbers are used for reference purposes only.
- Professional installation is strongly recommended for safety and to ensure proper engine performance. Incorrect installation can lead to severe engine damage.
About Sea Sierra
- Pro-Grade Standards — We supply marine and automotive parts engineered to OEM-level tolerances and rigorously tested for real-world conditions.
- Fast Global Fulfillment — With warehouses worldwide, we offer free standard delivery to most regions in 5–15 days and competitive expedited options.
- Manufacturer-Direct Value — By working directly with manufacturers, we provide fair pricing without compromising on materials or quality control.
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